The apparatus disclosed herein, in general, relates to a composite structure, and more specifically, relates to a radiolucent patient table top.
Conventional radiolucent patient tables comprise carbon fiber reinforced plastic (CFRP) skins with a foam core made of, for example, polyurethane or polymethacrylimides. CFRP table tops have twice as much X-ray permissibility as wooden table tops and five times that of plastic table tops. Improved radiolucency results in reducing a dosage of X-rays and associated health risks to a patient. The challenges associated with using a foam core in conventional radiolucent patient table tops are described below.
It is well known that the relative strength of composite skins made from foam cores is low when compared to the relative strength of honeycomb sandwich structures. Foam core sandwich structures have less fatigue resistance, and may structurally weaken over repeated loading and unloading of a patient table. Hence, manufacturers typically recommend a permissible working life period for these tables, after which they need to be replaced.
The radiolucent property of a foam core is less than that of carbon, and there is a possibility of contamination in the foam core made of polyurethane that may show up as errors during X-ray examination. The volume and amount of material in the table top must be reduced to a minimum. Non-radiolucent foreign material in the table top can result in a misdiagnosis of the patient.
Some X-ray table tops or their accessory components are made of thick sheets of carbon laminates. There is a need to reduce the quantity of carbon fibers and epoxy binders typically used in X-ray table tops to improve their permissibility to X-rays. Therefore, there is a need for low density carbon fiber table tops that are more radiolucent, that is, more permissible to X-rays.
Moreover, in an X-ray machine, the X-ray table top is required to be steady and therefore stiff in the field of detectors. The cantilever nature of an X-ray table exerts demanding loading on the X-ray table top. Foam core sandwich structures have poorer relative strength and stiffness when compared to honeycomb sandwich structures. In the aerospace industry, for structural applications, honeycomb cores are strongly preferred over foam cores. To improve stiffness, cantilevered foam core table tops have to be made thick. However, such thick table tops interfere with the easy maneuverability of the table tops, and therefore structural and ergonomic design compromises need to be made.
Hence, there is a long felt but unresolved need for a radiolucent patient table top that addresses the above mentioned problems of fatigue, increased thickness, reduced stiffness, and the need to reduce dosage of X-rays by improved radiolucency performance.